Method of inserting flexible strand members through a perforate fitting

ABSTRACT

A method and apparatus for inserting flexible cords or strands through holes in a perforate fitting for a high strength container such as a crash resistant fuel tank. A fixture is attached to one end of a plurality of elongated rods to support them parallel to each other in a position to match the hole pattern of the fitting to permit a plurality of the fittings to be slid onto the free end of the rods with each hole of each fitting having one of the rods passing therethrough. A plurality of cords or strands are looped around a hook on the free end of each rod and are fastened to a remote retaining member to position the strands in substantially axial alignment with the rods and provide an elongated extension of the rods so that each fitting may be slid from the rods onto the strands. The fittings are then spaced apart from each other on the strands and the strands are cut midway between each fitting leaving a group of strands through each hole of each fitting for attaching the fitting to a container wall.

United States Patent Bucher Feb. 6, 1973 [54] METHOD OF INSERTINGFLEXIBLE Primary Examiner-Charlie T. Moon STRAND MEMBERS THROUGH AAtt0meyF. W. Brunner et al. PERFORATE FITTING [57] ABSTRACT [75]Inventor: Robert W. Bucher, Glendale, Ariz.

A method and apparatus for inserting flexible cords or [73] Asslgnee:The Goodyear l Rubber strands through holes in a perforate fitting for ahigh P Akron Ohlo strength container such as a crash resistant fuel tank[22] Filed; July 19, 1971 A fixture is attached to one end of aplurality of elongated rods to support them parallel to each other in aPP 163,853 position to match the hole pattern of the fitting to permit aplurality of the fittings to be slid onto the free 52 us. Cl ..29 241,29 43 end mds with ,each hole each fitting having I 1 l l 3 one of therods passing therethrough. A plurality of [51 Int. Cl. ..B23p 19/04cords or Strands are looped around a hook on the free [58] Field ofSearch ..29/429, 433, 2,41; 223/99 end of each rod and are fastened to aremote retaining a member to position the strands in substantially axial[56] References C'ted alignment with the rods and provide an elongatedex- UNITED STATES PATENTS tension of the rods so that each fitting maybe slid I from the rods onto the strands. The fittings are then2,287,287 6/1942 Boltz ..L 29/24l paced apart from each other on thestrands and the 2,536,677 1/1951 Brunner el -29/241 X strands are cutmidway between each fitting leaving a 2901-819 9/1959 scllafian "29/241group of strands through each hole of each fitting for 390L270 9/1961Fnedma" attaching the fitting to a container wall. 3,239,928 3/1966.Baker ..29/24l g 8 Claims, 14 Drawing Figures PATENTEU FEB 6 I975 SHEET10F 3 INVENTOR.

ROBERT W. BUCHER ATTORNEY PATENTEU FEB 6 I973 SHEEI 2 OF 3 INVENTOR.ROBERT w. BUCH ER ATTORNEY PIC-3.5

PATENTEUFEB 6 I973 3.714.699

' sum 30F 3 FIGJO FlG.l|

INVENTOR.

FIG BY ROBERT W. BUCHER ATTORNEY METHOD OF INSERTING FLEXIBLE STRANDMEMBERS THROUGH A PERFORATE FITTING This invention relates to a methodand apparatus for inserting flexible cords or strands through holes in aperforate fitting for use in a crash-resistant fuel tank.

BACKGROUND OF THE INVENTION In the past, various attempts have been madeto design high strength fittings for fuel tanks such as those used onhelicopters or other aircraft to prevent the fitting pulling loose fromthe fabric wall of the fuel tank, thereby resulting in loss of fuel andcreating the possibility of fire or explosion. The problems of fittingspulling loose normally occur during a situation such as a crash wherethe fuel tank and fitting are subjected to high impact loads. Thisproblem is created by the fact that it is difficult to obtain adhesionbetween a metal fitting and a rubberized fabric wall. For this reason,various mechanical connecting means have been devised between the metaland the fabric to provide more positive interlocking of the fitting withthe fabric wall of the fuel rank. Various types of enlarged bead ringsretained in grooves in the metal fitting have been tried but have notproven satisfactory since under high impact loads there is a tendencyfor this type of connection to pull loose. One type of connection whichwas found to have superior strength was that in which a series of cordsor strands of material were interlocked with a metalfitting by passingthem through a series of holes arranged in a circumferential row nearthe periphery of the fitting and arranging the strands to extendradially outwardly from the fitting and then adhering the strands to therubberized fabric material. One of the problems encountered in producinga fitting in this manner is the time-consuming operation of passing thecords or strands through the holes in the fitting.

OBJECTS OF THE INVENTION It is a primary object of this invention toprovide a machine which will permit a large number of perforate metalfittings to be threaded with cords of strands simultaneously and therebyeliminate the time-consuming operation of individually stringing eachmetal fitting by hand. This and other objects of. the invention willbecome more readily apparent as the description proceeds in thefollowing specification and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS 1 FIG. 1 is a cross-sectional viewtaken in line 11 of FIG. 2 showing one embodiment of the apparatus ofthe invention;

FIG. 2 is a side elevational view of one embodiment of the apparatus ofthe invention;

FIG. 3 is an end view of the apparatus shown in FIG. 2 showing thestrand-retaining end of the apparatus;

FIG. 4 is an end view of the apparatus shown in FIG. 2 showing therod-support end of the apparatus;

FIG. 5 is a detailed cross-sectional view showing a typical fittingpositioned on the rods of the apparatus shown in FIG. 2;

FIG. 6 is a fragmentary cross-sectional view showing a typical fittingafter the strands or cords have been inserted through the holes and havebeen oriented in a radially outwardly extending direction;

FIG. 7 is a fragmentary plan view of the fitting shown in FIG. 6;

FIG. 8 is a simplified plan view of the apparatus shown in FIG. 2 with aseries of fittings arranged on the rods of the apparatus and with partof the strands placed in position on the apparatus;

FIG. 9 is a view similar to FIG. 8 but showing the fittings moved fromthe rods onto the strands in position for separation;

FIG. 10 is a side elevational view showing a fitting with strandstherethrough after it has been severed from its position on theapparatus shown in FIG. 9;

FIG. 11 shows a detailed view of the pulling ring guide used on theapparatus'previously described;

FIG. 12 shows a perspective view of the strandretainirig end assembly ofanother embodiment of the invention;

FIG. 13 shows a perspective view of the rod-supporting assembly of anembodiment of the invention used with the device shown in FIG. 12; and

FIG. 14 is a fragmentary side elevational view showing the embodimentshown in FIG. 13.

DESCRIPTION OF THE PREFERRED EMBODIMENTS generally by the numeral .1.The apparatus 1 is designed to support a plurality of fittings 2 such asthat shown in FIG. 5 on a plurality of parallel rods 3 extending througha circumferential row of holes 4 near the outer periphery of thefitting. A plurality of cords or strands 5 are positioned on theapparatus 1 in a manner which will be hereafter described and thefittings 2 are then slid from the rods 3 onto the cords 5 in spacedapart relationship. The cords 5 are then severed midway between eachfitting to. provide each fitting with a series of radially outwardlyextending strands 5 as shown in FIGS. 6 and 7. The strands 5 provide acompatible bonding structure which, when adhered to a rubberized fabricwall of a fuel tank, will provide a very strong bond. A typical exampleof how the strands 5 are bonded to a rubberized fabric fuel tank wall isillustrated in FIG. 1 of U.S. Pat. No. 3,534,987 in which I am aco-inventor.

Returning now to FIGS. 1 and 2, the apparatus 1 has a rod-supportassembly 6 on one end thereof and a strand-retaining assembly 7 ontheopposite end. The rod-support assembly has a bracket 8 attached to abase 9 by bolts 10. The bracket 8 has a centrally located hole 11 with abolt 12 passing therethrough and through a hole 13 in a circularrod-support plate 14. A spring 15 is mounted on the bolt 12 between thebracket 8 and the plate 14 to provide a friction clutch to resistrotation of the plate 14. On the opposite end of the apparatus, thestrand-retaining assembly 7 has a hinged bracket 16 which has a hinge17,. The bracket 16 is connected to the base 9 by bolts 18. The upperportion of the bracket 16 has a centrally located hole 19 therethroughwhich receives a bolt 20 which also passes through a hole 21 in acircular strand-retaining plate 22 which has a plurality of spaced apartradially outwardly extending pegs 23'which are screwed into threadedholes 24. A spring functions in the same manner as the spring 15 on theopposite end to provide a friction clutch to resist rotation of theplate 22. Both the plate 14 and 22 have a centrally located tube supportring 26 on the axially inner side thereof for supporting a hollow tube27. The rings 26 are connected to their respective plates by bolts 28 orother suitable means. The tube 27 is permanently fastened at therodsupport plate. The tube 27, however, is removably fastened at thestrand-retaining plate by a lock pin 30. When removed, the lock pinpermits the entire strandretaining assembly 7 to be swung about thehinge l7 and removed from the end of the tube to permit-the fittings 2to he slid onto the tube and then onto the rods 3.. The tube 27stabilizes the rod-support assembly 6 and strand-retaining assembly 7and permits the plate 14 and 22 to be rotated about the bolts 12 and 20when the strands S are being connected between the rods 3 and the pegs23. A fewer number of rods 3 and pegs 23 are shown in the drawings thanare actually used on most actual apparatus. This is merely for thepurpose of simplifying the illustration in the drawings. In actualpractice, the number of rods 3 which are used is'closer to thatillustrated in FIG. 4 in which a series of rods are shown in a circularpattern in close proximity to each other. This is necessary because, inmost instances, the holes 4 in fitting 2 are very close together aroundthe circumference of the fitting and one rod 3 is needed to pass througheach of the holes 4. The rods 3 function much in the same manner as aneedle for drawing a piece of thread through a hole. The only differenceis that instead of drawing the rod 3 and the cord or strand through thefitting, the fitting is first positioned on the rods 3 and then slidaxially off the rods onto the strands 5 which are threaded through ahook 31 at the free end of each rod 3. Usually there are fewer pegs 23required than there are rods with each peg being used in conjunctionwith several rods.

In operation of the apparatus, a group of fittings is strung in thefollowing manner. The lock pin 30 is removed to permit thestrand-retaining assembly to be swung downward away from the end of thetube 27. It should be mentioned that in some instances where thestringing apparatus 1 is relatively short in length for stringing asmall number of fittings that the tube 27 may not be necessary. Wherethe tube 27 is used, however, it is fastened to the rod-support assemblyas previously mentioned by the screws 29. Each of the rods 3 arefastened in a hole 32 in the plate 14 by a set screw 33'. The oppositeend of the rods 3 are free to receive a rod separator ring 34 which hasa similar hole pattern to the fittings 2 and holds the free ends of therods 3 to maintain the rods in parallel spaced relationship until thefittings 2 are placed thereon.

Asshown in FIG. 8, a plurality of fittings are slid onto the rods 3 witheach hole of the fitting having a rod passing therethrough. The rodseparator 34 is moved adjacent the rod support plate 14 when thefittings 2 are'positioned on the rods. A cord or strand separator ring35 is positioned on the rods 3 following the fittings 2. The cords orstrands 5 are then applied to the apparatus 1 by alternately passingthem through the hooks 31 at the ends of the rods 3 and then loopingthem around one of the pegs 23 on the strand-retaining plate 22. Afterthe strands 5 have en connected between each rod 3 and one of the'-" s23, the strand separator ring 35 is then moved off the rods 3 and alongthe strands 5 until it is adjacent the strand-retaining plate 22. Thestrand separator ring 35 aligns the strands 5 in parallel relationshipto receive the fittings 2. A pulling ring guide 36 shown in FIG. 11 isthen placed on each of the fittings 2 and the fitting is then movedalong the strands S in spaced apart relationship as shown in FIG. 9. Thering guide 36 is hinged at 37 to open for engaging each of the fittings2 and has a latch 38 for retaining it in a closed position once thefitting is engaged. Once the fittings 2 are spaced apart along thestrands 5, a piece of tape 39 is passed around the strands midwaybetween each of .thefittings. The strands 5 are then severed at thecenter of the tape so that each fitting along with a length of thestrands 5 as shown in FIG. 10 may be removed from'the apparatus 1. Thefitting and strands as shown in FIG. '10 is then ready for furtherprocessing for assembly into a fuel tank.

Many of the fittings to receive strands in this manner,

have a pair of wedge-shaped rubber filler rings 40 which extend radiallyoutwardly as shown in FIG. 6. When such filler rings are present, it isnecessary to bend them radially inwardly in order to permit passage ofthe rods 3 through the holes 4 as shown in FIG. 5. In order to hold thefiller rings 40 in this position, a circular band 41 is applied to eachfiller ring as shown in FIG; 5. This leaves the holes 4 exposed toreceive the rods 3. Once thefittings 2 are removed from the rods 3, thebands 41 may then be removed to permitthe filler rings 40 to return totheir normal position as shown in FIG. 6.

FIG. 7 illustrates the position of the filler rings in a plan view ofthe fitting 2.

FIGS. 12 through 14 illustrate another embodiment of the invention inwhich the fittings 41 lie in two different planes rather than in asingle plane as does the fitting 2. in a double plane fitting such asthe fitting 41, it is necessary to insert the strands in two differentsteps if a strand is being inserted in each plane at a different time.In FIG. 13 a fitting 41 has one of its planes positioned on a pluralityof rods 42 which are supported by a rod support 43. The rods are similarto the rods 3 in the previous embodiment and the strands to be insertedthrough the fitting 41 are connected between the hooks von the free.ends of the rods 42 and a plurality of pegs 44 on a strand supportbracket 45. Alternately between each of the fittings 41 is a rod spacer46 as shown in FIGS. 13 and 14 to hold the rods 42 inparallel spacedrelationship while the next adjacent fittings 41 are being placed on therods. After the fittings 41 are all positioned on the rods and thestrands are connected between the rods and the pegs 44 in the samemanner as described previously in the embodiment shown in FIGS. 1through'9', the same steps are followed as were applied to the previousembodiment. The fittings 41 are slid onto the strands and then taped andsevered from each other. After one plane of the fitting has been strungin this manner, the fitting is then turned and positioned on a set ofrods and the operation repeated tostring the other plane. I

While only two shapes offittings have been illustrated herein, it shouldbe understood that various shapes of fittings and various fittings havemulti-planes can be strung in a similar manner. One of the primaryfeatures of the invention is, of course, that a plurality of l claim: 1.An apparatus for inserting flexible strands through holes in a perforatefitting comprising:

A. a rod support means; 0

B. a plurality of elongated rods each having one end attached to thesupport means and the opposite end of each rod being a free end;

C. the rod support means holding the rods substantially parallel to eachother and in a relative position to conform to the position of the holesin the perforate fitting to permit a plurality of fittings to be slidonto the rods with each hole of each fitting having one of the rodspassing therethrough; and

D. a strand retaining means, spaced at a substantial distance from thefree ends of the rods, supporting a plurality of strands connected tothe free ends of the rods and to the strand retaining means in aposition to form an axial extension of the rod so that each fitting maybe slid from the rods onto the strands and positioned in spaced apartrelationship from each other along the strands whereby the strands maybe cut between each adjacent pair of fittings to permit removal of thefittings from the apparatus with each fitting retaining a plurality of30 strands in each hole of the fitting.

2. The apparatus claimed in claim 1 including means connecting the rodsupport means and the strand retaining means.

3. The apparatus claimed in claim 1 wherein the rod support means andthe strand retaining means are both pivotally mounted to be rotatableabout a common axis.

'4. The apparatus claimed in claim 1 including a rod separator having aplurality of holes conforming to holes in the fitting, said separatorbeing slidably mounted on the rods to retain the free ends of the rodsin spaced relationship to each other until the fittings are positionedon the rods.

5. The apparatus claimed in claim 1 including a slidable strandseparator to be moved longitudinally along the strands, after they areconnected between the free ends of the rods and the strand retainingmeans, to position the strands for receiving the fittings as they areslid on the rods.

6. The apparatus claimed in claim 1 wherein the fittings are generallycircular and the holes are located in a generally circular patternthereon.

7. The apparatus claimed in claim 1 wherein the fitting is a multi-planefitting and the strands are inserted simultaneously in the holes locatedin one plane of the fitting but independently from the holes of theother planes of the fitting.

8. The apparatus claimed in claim 1 including auxiliary gripping meansto engage each fitting and aid in sliding the fitting from the rod andalong the strands.

1. An apparatus for inserting flexible strands through holes in aperforate fitting comprising: A. a rod support means; B. a plurality ofelongated rods each having one end attached to the support means and theopposite end of each rod being a free end; C. the rod support meansholding the rods substantially parallel to each other and in a relativeposition to conform to the position of the holes in the perforatefitting to permit a plurality of fittings to be slid onto the rods witheach hole of each fitting having one of the rods passing therethrough;and D. a strand retaining means, spaced at a substantial distance fromthe free ends of the rods, supporting a plurality of strands connectedto the free ends of the rods and to thE strand retaining means in aposition to form an axial extension of the rod so that each fitting maybe slid from the rods onto the strands and positioned in spaced apartrelationship from each other along the strands whereby the strands maybe cut between each adjacent pair of fittings to permit removal of thefittings from the apparatus with each fitting retaining a plurality ofstrands in each hole of the fitting.
 1. An apparatus for insertingflexible strands through holes in a perforate fitting comprising: A. arod support means; B. a plurality of elongated rods each having one endattached to the support means and the opposite end of each rod being afree end; C. the rod support means holding the rods substantiallyparallel to each other and in a relative position to conform to theposition of the holes in the perforate fitting to permit a plurality offittings to be slid onto the rods with each hole of each fitting havingone of the rods passing therethrough; and D. a strand retaining means,spaced at a substantial distance from the free ends of the rods,supporting a plurality of strands connected to the free ends of the rodsand to thE strand retaining means in a position to form an axialextension of the rod so that each fitting may be slid from the rods ontothe strands and positioned in spaced apart relationship from each otheralong the strands whereby the strands may be cut between each adjacentpair of fittings to permit removal of the fittings from the apparatuswith each fitting retaining a plurality of strands in each hole of thefitting.
 2. The apparatus claimed in claim 1 including means connectingthe rod support means and the strand retaining means.
 3. The apparatusclaimed in claim 1 wherein the rod support means and the strandretaining means are both pivotally mounted to be rotatable about acommon axis.
 4. The apparatus claimed in claim 1 including a rodseparator having a plurality of holes conforming to holes in thefitting, said separator being slidably mounted on the rods to retain thefree ends of the rods in spaced relationship to each other until thefittings are positioned on the rods.
 5. The apparatus claimed in claim 1including a slidable strand separator to be moved longitudinally alongthe strands, after they are connected between the free ends of the rodsand the strand retaining means, to position the strands for receivingthe fittings as they are slid on the rods.
 6. The apparatus claimed inclaim 1 wherein the fittings are generally circular and the holes arelocated in a generally circular pattern thereon.
 7. The apparatusclaimed in claim 1 wherein the fitting is a multi-plane fitting and thestrands are inserted simultaneously in the holes located in one plane ofthe fitting but independently from the holes of the other planes of thefitting.